From patchwork Tue Jul 16 09:45:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eric Auger X-Patchwork-Id: 13734237 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DCA5FC3DA59 for ; Tue, 16 Jul 2024 09:47:40 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sTelk-0005tc-Oq; Tue, 16 Jul 2024 05:46:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sTelk-0005sz-0P for qemu-devel@nongnu.org; Tue, 16 Jul 2024 05:46:48 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sTelh-0000NQ-De for qemu-devel@nongnu.org; Tue, 16 Jul 2024 05:46:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1721123204; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gUjckqLbDLeSWm2r/UdxZCZJsU5t10ssHlVyg/zX46Y=; b=VjVkqQHv5WrpWqxVyxfrj2Q2tIzBqOev8EjTlBr/O0ga+vmVFZW/gi1sOyK2xcFnjbNAIj k8Dp3x9iBB8thc4W3hy8zMU3qoMgYgVWI5C1IAlARDoxRMU+QXit9LVlCfCHn7wsmHugZc KB8i/XaZugAuLmieX7VhzZ+xZnbRuU0= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-264-gqzJtYh8P_y9cqQfrLkWcA-1; Tue, 16 Jul 2024 05:46:40 -0400 X-MC-Unique: gqzJtYh8P_y9cqQfrLkWcA-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 913091955BFA; Tue, 16 Jul 2024 09:46:38 +0000 (UTC) Received: from laptop.redhat.com (unknown [10.39.192.185]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id BCAF13000183; Tue, 16 Jul 2024 09:46:33 +0000 (UTC) From: Eric Auger To: eric.auger.pro@gmail.com, eric.auger@redhat.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, mst@redhat.com, jean-philippe@linaro.org, peter.maydell@linaro.org, clg@redhat.com, zhenzhong.duan@intel.com, alex.williamson@redhat.com, jasowang@redhat.com Cc: yanghliu@redhat.com Subject: [PATCH 2/6] virtio-iommu: Remove probe_done Date: Tue, 16 Jul 2024 11:45:04 +0200 Message-ID: <20240716094619.1713905-3-eric.auger@redhat.com> In-Reply-To: <20240716094619.1713905-1-eric.auger@redhat.com> References: <20240716094619.1713905-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=eric.auger@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Now we have switched to PCIIOMMUOps to convey host IOMMU information, the host reserved regions are transmitted when the PCIe topology is built. This happens way before the virtio-iommu driver calls the probe request. So let's remove the probe_done flag that allowed to check the probe was not done before the IOMMU MR got enabled. Besides this probe_done flag had a flaw wrt migration since it was not saved/restored. The only case at risk is if 2 devices were plugged to a PCIe to PCI bridge and thus aliased. First of all we discovered in the past this case was not properly supported for neither SMMU nor virtio-iommu on guest kernel side: see [RFC] virtio-iommu: Take into account possible aliasing in virtio_iommu_mr() https://lore.kernel.org/all/20230116124709.793084-1-eric.auger@redhat.com/ If this were supported by the guest kernel, it is unclear what the call sequence would be from a virtio-iommu driver point of view. Signed-off-by: Eric Auger Reviewed-by: Cédric Le Goater --- include/hw/virtio/virtio-iommu.h | 1 - hw/virtio/virtio-iommu.c | 3 --- 2 files changed, 4 deletions(-) diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h index bdb3da72d0..7db4210b16 100644 --- a/include/hw/virtio/virtio-iommu.h +++ b/include/hw/virtio/virtio-iommu.h @@ -43,7 +43,6 @@ typedef struct IOMMUDevice { MemoryRegion bypass_mr; /* The alias of shared memory MR */ GList *resv_regions; GList *host_resv_ranges; - bool probe_done; } IOMMUDevice; typedef struct IOMMUPciBus { diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c index 4e34dacd6e..2c54c0d976 100644 --- a/hw/virtio/virtio-iommu.c +++ b/hw/virtio/virtio-iommu.c @@ -555,8 +555,6 @@ static int virtio_iommu_set_host_iova_ranges(VirtIOIOMMU *s, PCIBus *bus, current_ranges = sdev->host_resv_ranges; - g_assert(!sdev->probe_done); - /* check that each new resv region is included in an existing one */ if (sdev->host_resv_ranges) { range_inverse_array(iova_ranges, @@ -956,7 +954,6 @@ static int virtio_iommu_probe(VirtIOIOMMU *s, } buf += count; free -= count; - sdev->probe_done = true; return VIRTIO_IOMMU_S_OK; }